Hi, most people wore black. The immediate family were wearing white and wearing, for lack of better words, Taoist "outfits". Some parts were paper -- I guess to be burned later?
It was just as others have said. It was a room you walk into, there are some chairs scattered around. Before you go in the room, you give your envelop with money + $1 coin with your name written on it (they have envelopes). You are given back an envelope with a piece of candy, coin, and tissue, which you're supposed to use and get rid of before you go home (don't bring it home). Then, the priest (?) leads you when you enter to bow three times to the image of the deceased, and one time to the family that are kneeling near the image. We were also given some incense sticks to place at the alter. We then had a brief chance to say a few words to the family, who are actually milling about more than I expected, as a kind of host. Then we were directed to take a seat, and given paper pieces we roll up and put into a large bag (symbolizing coins/money?). Other people were already sitting around doing this rolling. There was also some photo albums of the deceased which we could look at. At one point the immediate family gave a very brief speech about the deceased. Then later some monks(?) began playing some music, but again, the coming and going continued, so it wasn't as if everyone stopped and "listened". After sitting around for awhile (20-30 mins?) I left, but before I could leave I had to again go through the ritual with the priest announcing and bowing (3x to image, 1x to family).
Cultural differences from my own culture: The place is was really cold and uninviting to me -- it almost felt like booking a hotel room, and in fact you're given a specific room number and time. I also felt it was sad that no one did anything collectively at the same time. I felt it was a little stressful and sad for the immediate family, who were quite young, to have to host this constant shuffle of people coming and going. So I guess there are other times and ways in which they can reflect and mourn?
Anyway, I've now told my immediate family if I die in Hong Kong please get me out and don't follow the HK traditions. Gosh, I don't think I even want anyone to enter a funeral home here on my behalf!
Regarding dress: I did wear a dark purple shirt under my black sweater -- whoops. But there was in fact a "host" from the funeral home, who asked me before bowing/incense if I were Christian because I didn't have to do that if I didn't want. So I think things are in fact a little relaxed. I was also told not to wear stones and accessories, no high heels, and don't say names or thank you or good bye. Also, I wanted to give a card to the family, but I was told not to at this time, so I sent it to them later.
Hope this might be useful to anyone else who has to go to a funeral.